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Discussing Bridge Percentages


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I was kibbing a team match today. At one point during a discussion of a possibility of a particular holding by a 1NT opener a kib claimed the percentage to be 55.555%. They were being totally serious about this.

 

My kneejerk reaction to this is always that giving percentages to anything smaller than a whole percentage shows a lack of understanding of the game and is, well, stupid.

 

What do you think?

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I was kibbing a team match today. At one point during a discussion of a possibility of a particular holding by a 1NT opener a kib claimed the percentage to be 55.555%. They were being totally serious about this.

 

My kneejerk reaction to this is always that giving percentages to anything smaller than a whole percentage shows a lack of understanding of the game and is, well, stupid.

 

What do you think?

Would you have a complaint if he had said "5 out of 9" or some such?

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I was kibbing a team match today. At one point during a discussion of a possibility of a particular holding by a 1NT opener a kib claimed the percentage to be 55.555%. They were being totally serious about this.

 

My kneejerk reaction to this is always that giving percentages to anything smaller than a whole percentage shows a lack of understanding of the game and is, well, stupid.

 

What do you think?

Would you have a complaint if he had said "5 out of 9" or some such?

less so, i think, but would be even happier with "slightly better than half"

 

i think i'm just being nitpicky

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I think expressions like 5/9 have some merit as they give hints towards the underlying assumptions. "Slightly better than 50%" sounds as if it is a guess based on some considerations too complicated to lead to a specific formula.

 

But yes, 55.555% looks a little silly. I saw at another forum, someone making a point like MatMat's and concluding by "I am pretty sure that 79.3261% of all forum posters agree with me".

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I think expressions like 5/9 have some merit as they give hints towards the underlying assumptions. "Slightly better than 50%" sounds as if it is a guess based on some considerations too complicated to lead to a specific formula.

 

But yes, 55.555% looks a little silly. I saw at another forum, someone making a point like MatMat's and concluding by "I am pretty sure that 79.3261% of all forum posters agree with me".

Why would 55.555% look silly and 5/9 have some merit?

 

The former is probably rounded and the later is presumably accurate.

 

I was taught from a young age to wherever possible leave numbers as fractions as converting to a decimal potentially lost accuracy.

 

Any number however accurately it is portrayed is subject to the implicit or explicit assumptions that have been made.

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Why would 55.555% look silly and 5/9 have some merit?

 

The former is probably rounded and the later is presumably accurate.

 

I was taught from a young age to wherever possible leave numbers as fractions as converting to a decimal potentially lost accuracy.

 

Any number however accurately it is portrayed is subject to the implicit or explicit assumptions that have been made.

I think this is a bit of an accuracy vs. precision thing for me.

 

I mean, we know the the result obtained to within one-one-thousandth or better... except that the actual odds might be a couple of percent one way or the other.

 

To have someone tell me that the percentage chance of p having a particular holding on a rather general auction using just an empty spaces calculation doesn't seem right.

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Shouldn't it have been 55.556%?

in Romania if your grades at the end of the term were 10 10 10 8, you'd get a 10 GPA, but if 10 10 8 and a 10 at a semester ending paper that has 25% weight in your GPA, you'd get a 9 for a GPA.

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Quoting bridge percentages to 4 significant figures is like a weatherman predicting a 49.27% chance of rain. We don't even believe he can be accurate when he rounds to the nearest 10 percentage points, so extra precision is meaningless. And even if he IS that accurate, what can we do with all that extra precision? You're either going to take an umbrella or not -- does a hundredth of a percentage make a difference in that decision?
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More accurate is not the same as more useful.

 

A thoughtful kib might have offered a choice or at least inquired about others' preferences regarding precision.

 

At the table - kibbing or playing -- I prefer whole numbers. No problem with 5/9.

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Quoting bridge percentages to 4 significant figures is like a weatherman predicting a 49.27% chance of rain. We don't even believe he can be accurate when he rounds to the nearest 10 percentage points, so extra precision is meaningless. And even if he IS that accurate, what can we do with all that extra precision? You're either going to take an umbrella or not -- does a hundredth of a percentage make a difference in that decision?

Do you take an umbrella everyday?

 

If not then at some point (range) over a range of 1/100 of a percent it does matter.

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The problem is is that if someone says a number as xx.xxx, it technically means that they know the answer to that number of decimal places of accuracy - for example, if I said 10.00mL as instead of 10mL, 10.00mL means (at worst) 10.00mL plus or minus 0.05mL, while 10mL means 10mL plus or minus 5mL (at worst).

 

Hence, when the kibber said 55.555%, he's technically saying the probability is 55.555% plus or minus 0.005%, which is ridiculous.

 

For example, if a person said they walked half a kilometer - did they travel 500.000m? No, they meant 500m, plus or minus 100m (200m?) or so.

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Hence, when the kibber said 55.555%, he's technically saying the probability is 55.555% plus or minus 0.0005%, which is ridiculous.

Would it have been ridiculous if he had said 5/9 instead of 55.555%?

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Hence, when the kibber said 55.555%, he's technically saying the probability is 55.555% plus or minus 0.0005%, which is ridiculous.

Would it have been ridiculous if he had said 5/9 instead of 55.555%?

TimG, so many of your posts are of this nature. I don't see the point.

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